Various types of mounting brackets have been constructed in the past to support heater coils within an electric heater for clothes dryer. In such brackets, the heater coils pass through ceramic grommets or other types of insulating bushings retained in brackets and then the brackets are mounted on a retaining wall. Such brackets attempt to provide a simple, efficient and cost effective way of securing the insulating bushings and for mounting the coils to the retaining wall.
It should be appreciated that to be cost efficient, the mounting bracket should be simple to construct and should be capable of being quickly secured and released without special tools. In this respect, attempts in the prior art to provide such a mounting bracket met with varying degrees of success.
For example, Canadian patent No. 771,787 of Kinney issued Nov. 14, 1967 describes a mounting assembly to be inserted into a pipe encasement. The assembly includes special ceramic insulators having a dove-tail base that is retained in a mounting strip and secured by means of jaws or clips that are then spot welded onto the mounting strip. This mounting assembly requires a special ceramic insulator and several interacting pieces as well as a welding step during installation.
U.S. Pat. No. 3,935,376 issued Jan. 27, 1976 to Cooper et al discloses a one piece ceramic insulator for supporting a ribbon type heating element. The ceramic insulator includes a slot located in a side surface of the insulator and includes a flat bearing surface over which the ribbon heating element is supported.
U.S. Pat. No. 4,250,399 issued Feb. 10, 1981 to Reynold King discloses an open coil electric heater having a rigid frame carrying ceramic coil supports which are detectors connected to the frame. Each coil support has an end formed with a cross slot to pass a part of the coil convolution or turn into the slot to be received in a groove. The coil is readily detachable and is inserted into the slot by twisting the coil at an angle of about 90 degrees relative to its normal direction of travel. The insulator supports only one-half of a convolution of the coil and requires considerable twisting by an operator to insert the coil into the ceramic insulator.
U.S. Pat. No. 4,848,567 issued Jul. 18, 1989 to Keith Howard et al teaches the use of an insulator having L-shaped brackets that receive different non-consecutive convolutions or turns of a coiled heating element.
U.S. Pat. No. 5,578,232 issued Nov. 26, 1996 to Roger Engelke discloses an open coil heater assembly comprising two parts which are secured relative to each other to squeeze between opposing hook shaped flanges the heating coil.
There is a need for a ceramic insulator which permits for easy assembly of a helically wound heating coil which can be assembled by an operator simply pushing the coil down onto the insulator without having the operator twist or bend the heating coil during the assembly process.